Synergy in a tactical carbine

by Lindsey Bertomen On Apr 1, 2008

The synergy concept says the sum of any given combination is greater than the sum of its individual parts. When the Law Enforcement Technology testing team mounted a Leupold 1x14mm Tactical Prismatic Riflescope on a Kel-Tec SU-16, the result was synergistic. The lightweight, compact package proved that a fast-handling carbine combo is neither expensive nor complicated. It is simply a matter of putting good optics on a good carbine.

The Kel-Tec SU-16 rifle is a self-loading, gas-piston operated carbine designed for the .223 Remington cartridge. It uses a receiver made of high-impact, reinforced polymer with a breech locking mechanism that resembles (and functions like) the proven AR-15. The rifle folds in half, pivoting just forward of the trigger guard. The two pieces of the forend fold down to make a bipod. The stock holds two 10-round magazines, which came with the rifle.

The Kel-Tec SU-16 comes in several variations. The model we used for this test is an SU-16A, which has an SKS style prominent hooded front sight. Several variants include shorter versions with compact front sights and lightweight, compact versions. The test version weighed 5 pounds and was 26.4 inches closed, which is light and compact already. For law enforcement use, we recommend Kel-Tec's compact forend conversion kit and 2-point sling kit, which gives officers more rail mounting surface for accessories.

Kel-Tec rifles use AR-15 magazines interchangeably, which allows officers to take advantage of the variety of products available. Our testing team liked Kel-Tec's polymer magazines but preferred metal ones with metal feed lips.

The Leupold Tactical Prismatic Riflescope is a 1x14mm optical system with one of the thickest main tubes in the business. Its etched circle dot reticle is more accurate than other projected reticles, which are inherently fuzzy.

The Leupold Tactical Prismatic Riflescope is designed for viewing with both eyes open. When adjusted correctly, officers are able to see a floating reticle, almost unaware of the scope tube. This gives officers an unrestricted field of view and depth perception while scanning and engaging. It is not a simple tube with a reticle. Users will quickly figure this out as it does have a specific range of eye relief.

It is completely compatible with the A.R.M.S. (Atlantic Research Marketing Systems) #22-34mm mounting systems, GG&G cantilever rings and a variety of low-light options.

The optic uses an etched reticle with a concentric dot and circle. This is an advantage over the projected reticles, which have less clearly defined edges. The reticle is adjusted for windage and elevation by incrementally decentering the objective lens, a feature completely distinct from standard optics.

The windage and elevation adjustments are raised, for easier access. Leupold suggests that they can be adjusted with a fingernail but they have rather stout clicks; we suggest using a coin in a pinch. We ran the adjustments around a few times and they always returned to zero. There is a floating zero dial where the officer can tailor his or her zero to the tactical situation. This design allows for confirmation and adjustment by feeling the instrument, making it an ideal low-light tool.

Leupold engineers designed an optic that can be illuminated by any light source. Although it comes with a simple illumination module that includes an LED lamp with a clamp assembly, virtually any source can light up the etched reticle.

The advantage of the etched reticle was quickly evident in low light. Projected reticles have fuzzy edges, particularly when the human eye is using more rods than cones. The Leupold reticle remains unchanged and is not battery dependent, keeping the objective in focus at all times.

The Leupold Tactical Prismatic Scope comes with an integrated mounting system, making it readily mountable on standard Picatinny rails. The mount comes with spacers to adjust the height above the receiver. It took only a few minutes to clamp our scope on the integrated Picatinny rail of the Kel-Tec. Leupold's included mounting screw was designed to accept a ratchet on the inside of the screw head and socket on the outside.

After mounting, one focuses the eyepiece so a well-defined reticle floats in the field of view, then fixes the focus in place with a locking ring. We adjusted it once and this adjustment worked for a wide variety of testers.

Our optic did not have any internal glare or reflections, regardless of the light source or ambient light. It was superimposed on the target with both eyes open. The shooter enjoyed a seamless, glare-free field of view.

Leupold uses a DiamondCoat2 scratch-resistant coating, designed to increase light transmission and abrasion resistance. When we first mounted the Leupold we tested the coating. We were getting ready to mount it during a test, when we … er … um … dropped it. Okay, perhaps this was an impromptu test but the optic did land directly, yes directly, on the corner of a rock. This was a "one-in-a-million" type of accident — not because optics testers lack butterfingers but because Leupold really recesses its lenses inside the metal case. Our ocular lens hit the corner of a rock on the center of the optic from several feet off the ground.

The rock mishap was separate from the other abuse users routinely give optics products. It did, however, prove one thing: The DiamondCoat2 scratch resistance works (and boy, are we glad). The Leupold Tactical Prismatic Riflescope was subjected to a number of other abuses, but none as harsh as smacking it on a rock.

Kel-Tec designed the SU-16 from the ground. Some of the features — like a reversible safety button — are a dramatic improvement in combat carbines. Kel-Tec has capitalized on some of the advantages of the front piston semi-auto design. For example, they make a pistol version (the Kel-Tec PLR). AR-15 pistol "clones" need a buffer tube in order to function, which sticks out of the back of a pistol version. Many manufacturers try to camouflage the buffer tube, which looks like an unsightly horizontal broomstick jutting out the back end. Kel-Tec's design separates it from this grouping, and as a result the pistol looks and works better.

The SU-16 was subjected to a significant amount of abuse, including allowing dirt and sand in the receiver and firing magazine after magazine. The synthetic receiver was designed to be forgiving, adding to its reliability and almost nonexistent recoil.

The Kel-Tec worked in dusty conditions when primed with a dry lubricant. We used the Smith & Wesson Dry Lube with Cerflon (distributed by Brownells). It was suitable for dry areas but we switched to Smith & Wesson Advanced Gun Oil when it wasn't dusty.

The SU-16 was not designed for precision matches, but it has acceptable accuracy at carbine ranges. It uses a simple trigger mechanism which was designed for safety and utility, not shooting matches. At 50 yards, it routinely produced 5-shot groups that could be covered by a quarter. Out to the 100-yard mark, it will center mass a torso-shaped target every time, which is all that should be asked of carbines. Most importantly, at high-risk car-stop distances, it was a precision instrument. With the Leupold Tactical Prismatic Riflescope, officers prevailed in multiple target scenarios.

However, the testing team generated some minor design suggestions for the SU-16. First, the team liked the way the firearm folds in half but wished it could pivot so that the entire trigger guard fits inside the magazine better to aid in protection. Second, the assembly pin, which is removed to pivot the rifle, should protrude a little with a ring so the user can grab it, rather than poke it through. The team suggests attaching this pin to the rifle, such as with a lanyard. The pin is one of those things that an officer should have extra in the pocket. The design suggestions have little to do with the unit's performance, of which there are no complaints.

For some reason the SU-16 is much louder than other carbines with similar features. Everyone noticed. It could be that impinged gas systems like the AR-15 carbines are just inherently quieter.

Kel-Tec SU-16 rifles, by design, are simple to field strip and replacement parts are inexpensive and easily obtained. There is a considerable body of knowledge among Kel-Tec owners who regularly report the reliability of the instrument. Our testing team had a chance to shoot the rifle in cold, soaking rain and higher than 100-degree weather. We subjected the rifle to a month of shooting without cleaning, which resulted in zero failures of any kind. We do not endorse or recommend this treatment, but the SU-16 is up to it.

This optic carbine combination had what law enforcement is looking for. With the advantage of a very wide field of view, two-eyed shooting and fast-handling carbine, officers at the patrol level can respond to armed suspects and active shooter emergencies. This combination also handles well in tight places. We haven't seen a patrol car gun rack for this rifle yet but we're sure one would be welcomed.

Our testing team ran hundreds of rounds through the SU-16 with the mounted optic. We never had as much as a road bump on our semi-auto superhighway. We did some things to the Leupold Tactical Prismatic Riflescope that we are hesitant to tell Leupold, and it survived.

The synergism the testing team strove for was about using the joint action of existing tools to create a superior tactical firearm combination. Bringing together the Leupold 1x14mm Tactical Prismatic Riflescope with the Kel-Tec SU-16 results in a package that creates the maximum advantage for users. Considering the price and low maintenance required by the products, agencies can equip an entire shift with this combination and still afford routine practice.

Lindsey Bertomen is a retired police officer who teaches administration of justice at Hartnell College in Salinas, California.